Method of handling material in the presence of compressed air



Oct. 6, 1925.

W. F. ROOS METHOD OF HANDLING MATERIAL IN THE PRESENCE OF COMPRESSED AIR Filed Feb. 15, 1923 2 Sheets-Shea: l

ATTORNEYS Oct; 6, 1925. 1,556,128.

W.-' F. ROOS umnon or HANDLING MATERIAL IN THE PRESENCE OF COMPRESSED AIR Filed Feb. 15.- 1923 2 sheets-sheet 2 INVHVTOR. I WILL/m7 f. Eves ATTORNEYS Patented Oct. 6, 1925.

U N'ITIED S T A'TES WILLIAM F. ROOS, 0F PELI-IAM ZMANOR, NEW YORK.

METHOD OF HANDLING "MATERIAL IN' THE PRESENCE OF'COMPRESSED AIR.

Application filed. February 15,1923. Serial No. 619,321.

To all to 710% it may concern:

Be it known that I, VVILLIAM F. Boos, a citizen of the United States, and resident of Pelham Manor, county of Westchester, and State of New York, have invented certain new and useful Improvements in Methods of Handling Material in the Presence of Compressed Air, of which the following is a. specification.

My invention relates to methods of handling material in the presence of compressed air and more particularly to methods of excavating in compressed air tanks, .caissons, or other compressed air zones and has for its object toremove the excavated material by means of an air conveyor in a manner to maintain the air pressure in said zone at an approximately constant point. My invention contemplates further-the utilization of the air conveyor for the introduction of a material such as concrete'or the like into said zone to replace the excavated material without materially varying the air pressure therein. The invention will be fully described hereinafter.

Reference is to be'had'to the accompanying drawings which, without defining the limits of the invention, show I diagrammatic examples of means for carrying out the improvedmethod; in said drawings Fig. 1 is a sectional elevation illustrating the invention as applied to caissons; Fig. 2 is a smaller view showing the invention applied in the digging of a tunnel; an

' Fig. 3 is a detail View partly in section of a part of the apparatus shown in Fig. 1.

In order that the invention may be fully understood I will first describe the elements illustrated in Fig. 1 and which comprise a caisson 5 constructed in any customary manner and provided with .the usual airlock 6 through which a bucket 7 may be raised and lowered by means of a cable 8 in the well-known way. In excavating with the present improved method in such caisson a stream or current of air is caused to circulate in a continuous path which is located partly outside of the caisson and whichcarries excavated material from the interior of the caisson to the exterior there of. This excavated material is then removed from saidstream of airat a point exteriorly of said caisson andithe air is caused to travel back into the caisson so that the pressure within the latter remains at an approximately constant point. The means whereby this may be accomplished comprises a suction tube 9 provided at its inner end with a suction nozzle 10 surrounded at a distance by a sleeve 11 which projects slightly beyond the free end of the nozzle 10 and is provided with air openings 12; it will be understood that the sleeve 11 is secured upon the suction tube 9 in any convenient manner. The outer end of the suction tube 9 communicates with the interiorof a collecting receptacle 13 mounted upon the caisson 5 by means of a support 14 and having an outlet 15 controlled by means of a valve 16. A valve 17 may be provided for-controlling the connection between the suction tube and the interior of the collecting receptacle 13; a baflie-plate 18 is fixed within the collecting receptacle 13 at a point opposite the communicating end of the suction tube 9. A return tube 9 leads from the upper end of the collecting receptacle .13 to a blower 19 mounted upon the caisson and communicating with the interior thereof by means of a pipe '20; a valve 21 may be located in the return tube 9 'for controlling the same.

In practice the blower 19 is set in motion and thus produces a suction in the collectingreceptacle 13 and in the suction tube 9 and at the same time introduces a stream ofair into the caisson 5 through the pipe 20 as indicated by the arrow in Fig. 1; in

d thismanner a stream of air is created which travels in a continuous path locatedpartly outside of the caisson as previously set forth. Under such conditions if the sleeve 11 is pushed into the material at the bottom of the caisson the suction in said tube 9 will carry said ,material upwardly thereiimdas a en the .upwardly passing current of air with excavated material reaches the collecting receptacle .13 it will impact against the balile plate 18 which will cause'the material to .be deflected downwardly and collected in said receptacle. his removal of the excavated material from the stream of air is facilitated by the air reaches the receptacle 13 its velocity decreases slightly because of the relatively increased area of'saidreceptacle 13; from the latter the vair passes through the return tube 9 by the action of the blower 19 and is passed back through the pipe 20 into the caisson 5; thus the pressure of the comreason of the fact that as pressed air in the caisson which the removal of air through the tube 9 tends to decrease is replenished and maintained approximately constant because a corresponding amount of air enters coincidentally through the pipe 20. By opening the valve 16 the collected material may be removed from the receptacle 13 through the outlet the discharge material may, as shown in Fig. 1, pass to a chute 22 and be delivered directly to a scow 23 or other suitable vehicle.

In Fi 2 which illustrates the digging of a tunnel, 5 represents a customary shield having an air-lock 6 of any well-known type. In excavating under such conditions the sleeve 11 is pushed into the material and carried by the current of air through the suction pipe 9 to the collecting receptacle 13 in the same manner as previously described. The air after having been relieved of the material in the receptacle 13 passes through the return tube 9" to the blower 19 by which it is propelled through the-pipe 20 back to the digging space in advance of the air-lock 6 as indicated by the arrow in Fig. 2. The material may be discharged 1 from the receptacle 13 directly into a cart or the like 23 for removal from the scene of the excavating. The method of excavating under conditions illustrated in Fig. 2 is the same as in Fig. 1 in that a stream of air is caused to travel in a continuous path which lies partly outside of the digging space in advance of the air-lock 6. Thus in this case also the pressure in said digging space is maintained at a substantially constant point by the introduction of air there: to to a degree corresponding to the removal of the air therefrom through the tube 9.

In some cases the method may be utilized for introducing concrete or other material into the excavation to replace the material removed; thus as shown in Fig. 2 the return pipe 20 may be provided with a hopper 24 controlled by a valve 25; by introducing concrete or other .material into the hopper 24- and then opening the valve 25 such material will be carried by the air through the return tube 20 into the digging space or its equivalent. i

In the illustrated examples the caisson 5 and the digging space in advance of the airlock 6 in the shield 5 represent compressed air zones in which material is being handled through the medium of an air conveyor either by being removed from said zone or introduced into the same. This handling of the material, that is either its removal from or its introduction into the presence of the compressed air, is accomplished with the improved method without reducing the 7 air pressure of said compressed air to any material extent and at no time to a point below that which is necessary to keep out enter the caisson or other compressed air zone; it thus never becomes necessary to remove large amounts of such muck, sand, ete., which have entered the caisson or other compressed air zone because of a drop in pressure therein. Men may be working in the caisson or in the tunnel removing large stones and the like which cannot be removed by the air conveyor and may also be doing other work whil the air conveyor is in op eration. Only a relatively small expendi- 7 ture of power is required to operate the improved method; for instance thirtyfive horse power will deliver approximately 2500 cubic "hr-ct o't air at one pound pressure which will convey approximately 500 pounds of material every minute, while five hundred horse power will deliver approximately 2500 cubic feet of air at one hundred pound pressure which will likewise convey 500 pounds of material every minute. The material collected in the tank may easily be load ed directly into a cart or scow by simply operating the proper valves. Mud as well as water, ete., can be removed from the compressed air zone without danger of breaking the machine elements because with the present method such materials do not pass through pump cylinders or do notcome into contactrwith any moving apparatus. The sleeve of the suction nozzle may be pushed directly into the material to be excavated and will dig it up without requiring it to be shovelled. The returning air may be used for conveying concrete, cement, mortar, ete., into the caisson or other compressed air zone where it may be used wherever required and where if desired it may be conducted to its point of use by a flexible hose. Furthermore the method may be used and started with any degree of pressure existing in the caisson or other compressed air zone. I

In some casesthe blower may be dispensed with in which case the collecting receptacle 13 may be provided with an air vent 13 which is large enough to cause the small difference in air pressure between the caisson or its equivalent and the collector which is required to operate the method. This, however, is a more expensive method to operate because the air escaping through the air vent must be replaced in the caisson or its equivalent. This is more expensive because without a continuous enclosed air-circuit as representedby the illustrated examples it is necessary to admit air from atmospheric pressure into the caisson or its equivalent at the pressure therein.

The method is capable of being efflciently utilized wherever excavatingor other handling of material in the presence of compressed air or specifically in a compressed air zone is taking place and where it is desirable to maintain the pressure in said zone at an approximately constant point.

hat is to say, the enclosed system as de scribed whether used for removing material from a compressed air zone or introducing material into said zone, will always maintain the air pressure in said zone against any material decrease or increase as the case may be.

Various changes in the specific form shown and described may be made within the scope of the claims without departing from the spirit of the invention.

I claim:

1. The method of handling material in the presence of compressed air normally sealed to the atmosphere which consists in moving the material by means oi": a fluid conveyor in a manner to maintain the pressure of said compressed air at an approximately constant point.

2. The method of handling material in a compressed air zone normally sealed to the atmosphere which consists in conveying the material by means of a fluid stream and coincidentally adjusting the air pressure in said zone in a manner to maintain it approximately constant.

3. The method of excavating in the presence of compressed air normally sealed to the atmosphere which consists in removing excavated material by means of fluid conveyance. in a manner tomaintain the pressure of said compressed air at an approximately constant point.

4:. The method of excavating in a compressed air zone normally sealed to the at mosphere which consists in conveying the excavated material from said zone by means of an air conveyor and coincidentally adjusting the air pressure in said sealed zone in a manner to maintain it approximately constant.

5. The method of excavating in a compressed air zone normally sealed to the atmosphere which consists in removing the excavated material from said zone by air suction and coincidentally introducing airto said sealed zone to maintain the air pressure therein at an approximately constant point.

6. The method of excavating in a compressed air zone-normally sealed to the atmosphere which consists in removing excavated material from said zone by means of a stream of air, separating the material from said stream of air and returning the latter 'to said sealed zone whereby the air pressure therein is maintained at an approximately constant point.

7 The method of excavating in a compressed air zone normally sealed to the atmosphere which consists in maintaining a stream of air in acontinuous path located partly outside of said sealed zone whereby excavated material is conveyed from said sealed zone and removing said material from said stream of air at a. point exteriorly of said sealed zone.

8. The method of excavating in a compressed air caisson normally sealed to the atmosphere which consists in removing excavated material from said sealed caisson by air suction and coincidentally replenishing the air in said sealed caisson to maintain the air pressure therein at an approximately constant point.

9. The method of excavating in a normally sealed tunnel under compressed air which consists in removing excavated material from said sealed tunnel by air suction and returning the air to said sea-led tunnel to maintain the air pressure therein at an approximately constant point.

10. An apparatus for handling material in the presence of compressed air comprising a chamber normally sealed to the atmosphere and containing air under pressure, a conveying circuit located partly within said sealed chamber and extending exteriorly thereof, means for creating motion in a fluid current through said circuit and back to said sealed chamber and means located in said circuit exteriorly of said chamber whereby the velocity of said fluid is reduced at a predetermined po-int in said current.

11. The combination of a caisson normally sealed to the atmosphere and adapted to con tain air under pressure, a. conveying circuit having its opposite ends in communication with the interior of said sealed caisson, said circuit being located partly within the latter and extending exteriorly of said sealed caisson, means for creating motion in a fluid current through said circuit and back to said sealed caisson and means in said circuit located exteriorly of said sealed caisson whereby the velocity of said fluid is reduced at a predetermined point in said current.

12. The combination of a chamber normally sealed to the atmosphere and arranged to contain fluid under pressure, a device located exteriorly of said sealed chamber, a fluid conduit communicating with said device and said sealed chamber for conveying material from one to the other by means of a fluid current and means connected with said sealed chamber arranged to compensate for any changes in the fluid pressure therein resulting from an operation of said fluid current through said fluid conduit whereby the fluid pressure in said sealed chamber is maintained at an approximately constant point.

13. The combination of a chamber normally sealed to the atmosphere and arranged to contain fluid under pressure, a separator located exteriorly of said sealed chamber, a fluid conduit connecting said device With said separator, means whereby a current of fluid is caused to pass through said conduit and back to said sealed chamber to maintain the fluid pressure therein at an approximate 1y constant point and a hopper connected with said conduit at a point exteriorly of said chamber for introducing material into said conduit from the exterior of the sealed chamber.

In testimony whereof I have hereby signed this specification.

WILLIAM F. R008. 

